If your email client's security prevents dealing with attachments at all,
you can usually change a setting in the client's setup. For example, in
Outlook Express, on the Security tab of Tools | Options, there is a check
box for "Do not allow attachments to be saved or opened that could
potentially be a virus." This box is checked by default, but you can clear
it. Still, do not open Word documents from attachments (which is a good way
to lose your editing even if you don't get a virus); instead save the file
to your My Documents folder (or anywhere else on your HD) and open it from
there.